##class CityFunctions:
##    def __init__(self,city,country):
##        self.city = city
##        self.country = country
##        
##    def city_country(self):
##        city_country = self.city.title() + ',' + self.country.title()
##        return city_country
##
##    @staticmethod
def city_country(city,country,population=None):
    if population:
        city_country = city.title() + ',' + country.title() + '-population' + ' ' + str(population)
    else:
        city_country = city.title() + ',' + country.title()
    return city_country 
